Abstract: | Many astrophysical phenomena involve an abrupt release of a large amount of energy close to the surface of a large body. Examples include impacts on a terrestrial planet, outbursts from a neutron star while inside the common envelope of a giant star and a supernova explosion in a giant molecular cloud. In this talk I will present a new universal analytic solution that can describe the shock wave in all these scenarios. I will show that this shock wave satisfies a new kind of conservation law that lies somewhere in between energy and momentum conservation. This conservation law opens the door to a myriad of insights about a wide range of physical problems: the size and shapes of craters, atmospheric mass loss from giant impacts, oblique shock breakout and the survival of molecular clouds. |